Note: Descriptions are shown in the official language in which they were submitted.
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TITLE
TANDEM APPLICATION OF SOIL AND STAIN RESISTS TO CARPETING
FIELD OF THE INVENTION
This invention relates to a process for the application of a fluorochemical
soil resist and a stain resist to polyamide, silk, and wool carpets in a
tandem
application without any intervening finishing step. The process allows
application
of stain and soil resists that would be incompatible in a single bath
coapplication
without adversely affecting the performance of either.
BACKGROUND OF THE INVENTION
Polyamides, silk, and wool fibers are subject to staining by a variety of
agents, particularly acid dyes such as FD&C Red Dye No. 40, commonly found in
soft drinks. Various stain resist agents have been used, including sulfonated
phenol formaldehyde condensates and polycarboxylic acids such as those derived
from methacrylic acid or malefic acid. Usually the stain resist agents are
applied
from an aqueous medium under conditions of controlled pH.
Additionally, polyamide, silk, and wool fibers are subject to soiling.
Several of the currently used soil resist agents for nylon carpets are based
on
polymers derived from perfluoroalkylethyl alcohols. Typically the
perfluoroalkylethyl alcohol derivatives are incorporated into acrylic or
urethane
polymers for application by foam, padding or spraying to various substrates.
Fluorochemical soil resist agents offer little protection from stains caused
by acid dyes. Since the fluorochemical soil resist agents do not exhaust from
aqueous solutions, they are usually applied in a separate operation from stain
resists. Coapplication of the stain resist and soil resist would be more
economical.
Jones Jr. in U.S. Patent No. 5,520,962 uses compatible soil/stain resists in a
single
bath. However, coapplication of conventional stain resists and soil resists
often
does not provide the desired properties. Additionally, coapplication
techniques
are not appropriate to all combinations of stain resists and fluorochemicals,
especially when the two materials are incompatible or when one chemical
impedes the exhaust efficiency of the other.
The incompatibilities result in such problems as phase separation and
precipitation in the bath, increased bath viscosity, reduced wetting,
excessive
foaming, or other unacceptable physical changes which make the stain resist
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and/or the fluorochemical soil resist not perform on the carpet. Causes for
these
problems include incompatibilities in pH, concentration, mixed charges
(e.g., anionic and cationic components), salt concentration, temperature, or
other
factors. For applications by exhaustion there may be competition between the
soil
resist and stain resist exhaust rates onto the fiber.
The nature of the competition between the fluorochemical and stain resist
exhaust rates onto the fiber is not well understood. However, it is known that
the
single step or coapplication of compatible stain resists and fluorochemical
soil
resists typically encounters conflicting process requirements for optimum and
efficient application for one chemical treatment or the other. Although both
the
stain resist and fluorochemical can be deposited onto the carpet, their final
performance is not as good as when separate applications are employed.
Various processes for the separate application of stain and soil resists to
carpets have been attempted. Typically a stain resist is applied followed by
several finishing steps. This is then followed with a separate application of
the
fluorochemical soil resist followed by finishing steps. Attempts to apply both
the
stain resist and soil resist under stain resist conditions have resulted in
poor
performance due to the competition between the fluorochemical and stain resist
exhaust rates onto the fiber. Attempts to apply both the stain and soil resist
under
the soil resist application conditions have also resulted in various product
deficiencies.
It is desirable to have a process in which both the agents conferring soil
and stain resistance can be applied whether or not the agents are mutually
compatible, and for the finished product to display optimum performance for
both
treatments. The present invention describes such a process that allows both
soil
and stain resists to be applied in tandem with a single finishing step.
SUMMARY OF THE INVENTION
The present invention comprises a process for rendering carpet fiber
resistant to stains and soil comprising
a) applying to carpet fiber a f rst aqueous medium of at least one stain
resist,
b) applying to carpet fiber a second distinct aqueous medium of at
least one fluorochemical soil resist without any intervening
steaming or rinsing, and
d) drying the carpet.
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DETAILED DESCRIPTION OF THE INVENTION
The process of the present invention comprises the application of a
fluorochemical soil resist and a stain resist separately, sequentially, in any
order,
followed by a final drying step. The process of the present invention
simplifies
the application process by making optional any finishing step, such as
steaming or
rinsing between the tandem application of the stain resist and the soil
resist.
Better stain and soil resist performances are obtained using the process of
the
present invention compared to a process in which the stain resist is applied
followed by one or more finishing steps such as steaming, rinsing, vacuum
extraction, or drying followed by the soil resist being applied and cured. The
advantage over prior art single coapplications is that incompatible stain and
soil
resists can be used in this new process without adversely affecting the
performance of either.
"Exhaustion" as used herein is a process by which a chemical treatment is
transferred to a carpet by applying a water solution containing the chemical
to the
carpet. The conditions of the water solution are optionally changed (i.e.,
heating
the wet carpet, changing the pH, adding a precipitant, etc.). Subsequently,
the
excess water and any chemical not bound to the carpet fiber can be removed
from
the carpet by physical means such as centrifugal separation or vacuuming. In
an
exhaust process a soluble bath component is absorbed from the bath onto the
fiber.
In exhaust applications, the water soluble chemical is partitioned between the
water and the fiber, preferentially absorbing on the fiber. In such cases, the
bath
concentration is depleted more than in proportion to the wet pickup.
Fluorochemicals used as soil resists do not, strictly, exhaust because the
fluorochemical soil resists used for carpets are not water soluble. The
fluorochemical soil resist is either dispersed or emulsified in water with
surfactants. The pH, the chemical interactions, and the temperature affect the
ability of the surfactant to keep the fluorochemical dispersed or emulsified
in
water. The fluorochemical soil resist is precipitated onto the carpet pile.
A "coating" application is a process by which a chemical treatment is
applied to a carpet in a water solution and water is evaporated by drying,
leaving
all of the non-volatile chemicals applied from the water solution as a coating
on
the carpet fibers. In nonexhaust applications, such a coating operation, the
amount of chemical agent transferred to the fabric is determined solely by
chemical concentration in the bath and the wet pickup of the carpet by the
bath, as
only water is removed when the carpet is heated and dried.
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"Extraction" is a physical process to remove excess water and water
soluble chemicals from the carpet using such means as centrifugal separation,
passing the carpet over a vacuum slot, or passing the carpet between two or
more
closely spaced rolls to squeeze or nip the water from the carpet. A typical
extraction step lowers the wet pickup of the carpet to between 50% and 80% of
the dry carpet weight, depending on pre-extraction wet pickup of the carpet
and
the strength and efficiency of the vacuum. Extraction is commonly used when
the
wet pickup exceeds about SO% to reduce energy requirements for drying.
The term "bath" as used hereinafter refers to the aqueous solution or
dispersion ready for application to the carpet. Both the soil resist and the
stain
resist baths are prepared conventionally according to the manufacturers'
recommendations. Stain resist baths have a pH range between about 1 and about
6 and preferably between about 2 and about 3; soil resist baths have a pH
range
between about 1 and about 10 and preferably between about 4 and about 8.
The "wet pickup" is the total weight of applied liquid contained in the
carpet divided by the weight of the original dry carpet, expressed as a
percentage.
In the process of the present invention, a bath containing a soil resist is
applied to the carpet at a low wet pickup of from about 5% to about SO%,
preferably from about 5% to about 25%, and more preferably from about 10% to
about 15%. Then, without any intervening finishing step such as steaming,
rinsing, extraction, or drying, a second distinct bath containing a stain
resist is
applied to the carpet at an additional wet pickup of from about 20% to about
500%, preferably from about 20% to about 400% and more preferably from about
70% to about 250%. In one application method, the carpet is passed through the
bath, but other application methods as noted below are suitable for use
herein.
The carpet, with total wet pickup in the range of 25% to 525%, and preferably
80% to 265%, is then dried. Both the stain and soil resists exhaust onto the
fiber
during application. Steaming, rinsing and extraction steps are optionally
employed prior to drying.
The baths used in the present invention typically contain other components
such as one or more acids to adjust pH including sulfuric, phosphoric, and
sulfamic acids and blends thereof; salts such as calcium, sodium, potassium,
or
magnesium sulfate; anti-foaming additives such as silicones or hydrocarbons;
and
foaming or wetting agents such as alkyl sulfonates, ethoxylated fatty acids,
ethoxylated fatty alcohols, alkyl aryl sulfonates.
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The steaming, rinsing, and extraction steps are optional but preferred in
most applications. When these steps are omitted, the dried carpet may exhibit
harshness to the hand and may be more susceptible to fading and yellowing on
exposure to sunlight and/or nitrogen oxides. The total wet pickup on the
carpet
usually should be kept to a minimum (normally less than 100% total wet pickup)
when these steps are omitted. This limited wet pickup may cause the
penetration
of the stain and soil resist chemicals into the carpet pile to be
insufficiently
thorough to provide adequate protection of the bottom of the carpet tufts.
However, in certain applications where these product qualities are less
important,
the reduced energy costs and the increased mill capacity associated with the
steaming and/or rinsing steps justify their omission.
The typical conditions for steaming, when it is employed, are to use
saturated steam at 210 to 214°F (99 to 1 O1 °C), for 20 to 200
seconds, and
preferably saturated steam at 211 to 212°F (99.4 to 100°C) for
40 to 100 seconds.
Typical conditions for rinsing and extraction, when employed, are rinsing with
water at between 40 to 175°F (5 to 80°C) and with rinse wet
pickup between
about 40% and about 200%, and with rinse water raising the total wet pickup to
between about 400% and about 600%, followed by extraction to between about
40% to about 100% wet pickup. However, rinsing and extraction conditions are
not generally critical. The optional extraction is typically used prior to
drying
when the total wet pickup in any carpet process exceeds about 50%. This is the
point at which extraction before drying becomes more efficient than just
drying all
the water. Any chemical treatment that is not bound to the carpet fiber prior
to the
extraction step is lost in proportion to the percentage of water extracted.
Conditions for drying suitable for use in the present invention are to use hot
air or
radiant heat until the carpet face fiber reaches between 180 and 300°F
{82 to
150°C) and preferable between 220 and 280°F (104 to
138°C).
In alternative embodiments of the present invention, spray, foam, flex-nip,
nip (dip and squeeze), liquid injection, overflow flood, and other application
methods well known to those skilled in the art, are suitable for use for
tandem or
sequential application of the stain and soil resists to the carpet, utilizing
the baths
described above. For instance, the low wet pickup bath system can be
interchanged with low wet pickup spray or foam systems, and the high wet
pickup
bath system can be interchanged with other high wet pickup systems, e.g., flex-
nip
system, foam, pad, or flood. The method employed determines the appropriate
wet pickup and whether the application is made from one side of the carpet
(spray
and foam applications) or both sides (flex-nip and pad).
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In spray applications, the spray is applied according to the soil resist and
stain resist manufacturer's recommendations, typically in single or double
overlapping patterns to the top of the carpet pile. A spray application
pressure of
less than 60 psi (414 kPa) is used with a wet pickup of from about 5% to about
50% and usually about 10% to about 15% based on the carpet weight for
fluorochemical soil resists, and a wet pickup of from about 20% to about 200%
for stain resists.
In foam applications, the foam is applied according to the soil resist and
stain resist manufactures' recommendations, typically in direct puddle
applicators
with a press roll or an injection manifold. It is applied to the top of the
carpet pile
with a wet pickup of typically of from about 5% to about 50% and preferably
from about 10% to about 15% based on the carpet weight for fluorochemical soil
resists and a wet pickup of from about 20% to about 200% for stain resists.
Foam
densities range between about 250 to about 50 grams/liter.
In flex-nip and in dip and squeeze applications, the carpet is passed into
the center of a trough of an aqueous bath containing stain resist, acid,
surfactants,
and optionally salts, or other components prepared according to the stain
resist
manufacturer's recommendations. The carpet then exits the bottom of the trough
between an air bladder with pressure of approximately 3-10 psi (21-69 kPa).
This
results in a wet pickup of between about 150% and about 300% as a ratio of the
dry carpet weight, and typically about 200% wet pickup.
Other application methods, such as liquid injection and overflow flood, are
also suitable for use in the present invention and constitute alternative
methods for
the application of treatment baths to carpet.
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The following table provides a listing of methods of application for the
stain resist and soil resist, together with typical and preferred wet pickup
values
for each method and each resist:
Application Typical Preferred
Method Wet Pickup
Pickup Range
Range (%)
(%)
Stain resists:
Flex-nip 150 - 350 200 - 300
Flood 100 - 500 200 - 300
Foam 20 - 200 50 - ISO
Pad 100 - 500 200 - 300
Spray 20 - 200 50 - 150
Fluorochemical
soil resists:
Foam 5 - 50 10 - 15
Spray 5 - SO 10 - 15
Many variations of the conditions for spray, foam, flex-nip, flood, and pad
applications are well known to those skilled in the art and the preceding
conditions are provided as examples and not are intended to be exclusive.
In yet another embodiment of the invention, the stain resist is applied
before the soil resist. The sequential application is followed by drying.
Steaming,
rinsing and extraction steps are optional, and when employed are at the
conditions
previously discussed. Chemical considerations determine whether the soil
resist
application is preferably before or after the stain resist application. The
important
distinction of this invention is that the soil and stain resists are applied
separately
and both are applied before any finishing step.
Thus the practice of the present invention includes both the application
sequence stain resist then soil resist and the application sequence soil
resist then
stain resist. The application sequence is dictated by the properties of the
carpet,
the manufacturing equipment available, and the chosen chemical treatments.
Typically, spraying the fluorochemical soil resist after applying the stain
resist
gives better fluorine retention but poorer stain resistance than when the
stain resist
is applied before the soil resist.
A wide range of stain resists and soil resists are suitable for use in the
practice of the present invention. Suitable stain resists are polymers
containing
phenol-formaldehyde, methacrylic acid, malefic acid, sulfonated fatty acids,
and
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blends of the above. Suitable soil resists are polymers containing
fluorochemical
residues with the most preferred being cationically dispersed. The use of
cationic
fluorochemicals in combination with anionic stain resists typically gives
better
fluorine retention.
Suitable stain resists for the practice of this invention include, but are not
limited to, phenol formaldehyde polymers or copolymers such as CEASESTAIN
and STAINAWAY (from American Emulsions Company, Inc., Dalton, GA),
MESITOL (from Bayer Corporation, Rock Hill, NC), ERIONAL (from Ciba
Corporation, Greensboro, NC), INTRATEX (from Crompton & Knowles Colors,
Inc., Charlotte, NC), STAINKLEER (from Dyetech, Inc., Dalton, GA),
LANOSTAIN (from Lenmar Chemical Corporation, Dalton, GA), and SR-300,
SR-400, and SR-500 (from E. I. du Pont de Nemours and Company, Wilmington,
DE); polymers of methacrylic acid such as the SCOTCHGARD FX series carpet
protectors (from 3M Company, St. Paul MN); and sulfonated fatty acids from
Rockland React-Rite, Inc., Rockmart, GA).
Suitable soil resists for the practice of the present invention include, but
are not limited to, fluorochemical emulsions such as AMGUARD (from American
Emulsions Company, Inc., Dalton, GA), SOFTECH (from Dyetech, Inc., Dalton
GA), LANAPOL (from Lenmar Chemical Corporation, Dalton, GA),
SCOTCHGARD FC series carpet protectors (from 3M Company, St. Paul, MN),
NK GUARD (from Nicca USA, Inc., Fountain Head, NC), UNIDYNE (from
Diakin America, Inc., Decatur, AL), and ZONYL 555, N-130 and N-119 (from
E. I. du Pont de Nemours and Company, Wilmington, DE).
Results indicate that even if the stain and soil resists are compatible and
can be coapplied simultaneously from a single bath, sequential tandem
application
results in better performing stain and soil resists than when the materials
are
coapplied in the same bath. As shown in the examples, a coapplication of a
stain
resist and soil resist demonstrated poorer performance than sequential tandem
application of a soil resist followed by application of a stain resist.
In the invention described here, the fluorochemical and the stain resist are
applied separately without an intervening finishing step. The process of the
present invention is useful to provide a better degree of stain and soil
resistance
than when the stain resist treatment is applied, steamed, and then the soil
resist is
applied. It is also useful for employing incompatible stain and soil resists
without
adversely affecting the performance of either. Stain and soil resistance as
well as
water repellency are desired attributes for residential and commercial
carpeting.
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This invention gives maximum repellency on the carpet in a more economic
process.
The following testing methods were employed in the examples.
Method 1 Determination of Oil and Water Repellence
1.a. Oil Repellency Test
Oil repellency was measured according to the American Association of
Textile Chemists and Colorists (AATCC) Standard Test 188-1978, which is based
on the resistance of treated fiber or fabric to penetration of oils of varying
surface
tensions at a scale of 0 to 8. A rating of 8 is given to the least oil
penetrating
(most oil repellent) surface. Results for untreated, control, and example soil
tests
by this procedure are shown in Table 2 below.
1.6. Water Renellencv Test
Water repellency was measured according to DuPont "Teflon"
(Wilmington, DE) Standard Test Method #311.56. After conditioning for 4 hours
at 70°F (21 °C) and 65% relative humidity, the fabric is placed
on a flat level
surface. Three drops of the selected water/isopropanol mixture (see Table 1,
below) are placed on the fabric and left for 10 seconds. If no penetration has
occurred, the fabric is judged to "pass" this level of repellency and the next
higher
numbered test liquid is tested. The fabric rating is the highest numbered test
liquid that does not wet the fabric.
Table 1
Water/Isonropanol Mixtures for the Water Repellence Test
Composition
(wt.
%)
Water Repellency
Rating Water Isopropanol
Number
1 98 2
2 95 S
3 90 10
4 80 20
5 70 30
6 60 40
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A rating of 0 indicates no water repellency, a rating of 6 indicates
maximum water repellency. Results for untreated, control, and example soil
tests
by this procedure are shown in Table 2 below.
Method 2 24-Hour FD&C Red No. 40 Staining
S Stain Test (AATCC 175-1991)
Acid dye stain resistance was evaluated using a procedure based on the
American Association of Textile Chemists and Colorists (AATCC)
Method 175-1991, "Stain Resistance: Pile Floor Coverings." A staining solution
was prepared by mixing water and sugar sweetened cherry Kool-Aid~ according
to package directions. Alternatively the solution is prepared by mixing 0.2 g
of
FD&C Red No. 40 and 3.2 g of citric acid in one liter of deionized water. The
carpet sample to be tested was placed on a flat non-absorbent surface and a
hollow
plastic cylinder having a 3-inch (7.6 cm) diameter was placed tightly over the
carpet sample. Twenty ml of staining solution was poured into the cylinder and
the solution was allowed to absorb completely into the carpet sample. The
cylinder was then removed and the stained carpet sample was allowed to sit
undisturbed for 24 hours, after which it was rinsed thoroughly under cold tap
water and squeezed dry.
The carpet sample was then visually inspected and rated for staining
according to AATCC Red 40 Stain Scale. A stain rating of 10 is excellent,
showing outstanding stain resistance, whereas 1 is the poorest rating,
comparable
to an untreated control sample. Results for control and example stain tests by
this
procedure are shown in Table 2 below.
Method 3 Shampoo-Wash Durability Test
A treated carpet specimen, approximately 3 x 5 inch (7.6 x 12.7 cm), is
submerged for 5 minutes at room temperature in a detergent solution consisting
of
sodium lauryl sulfate (dodecyl sodium sulfate) such as "Duponol WAQE" ( 1.5 g
per liter) and adjusted with dilute sodium carbonate to a pH value of 10. The
specimen is then removed, rinsed thoroughly under tap water, de-watered by
squeezing, and air-dried. The dry carpet specimen is then tested according to
the
stain test described above. Results for the examples and comparative example
are
show in Table 2 below.
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EXAMPLES
The following soil resists, stain resists, and other materials were used in
the examples.
ZONYL 555 Carpet Protector is a cationic fluorochemical soil resist
prepared according to US 4,958,039 and available from E. I. du Pont de Nemours
and Company, Wilmington DE.
N-130 and N-119 are anionic polyfluoro nitrogen-containing soil resists
prepared according to US 5,580,645 using sodium alkyl sulfonates as the
surfactant to stabilize the emulsion. The two soil resists are available from
E. I. du Pont de Nemours and Company, Wilmington DE and are anionically
dispersed.
SR-300, SR-400. and SR-500 are water soluble anionic stain resists
available from E. I. du Pont de Nemours and Company, Wilmington DE. SR-300
is prepared according to U.S. Patent No. 5,057,121, SR-400 is prepared
according
to U.S. Patent No. 4,883,839, and SR-500 is prepared according to U.S. Patent
No. 5,460,887.
Duponol WAQE is a mixture of sodium lauryl sulfates available from
Witco Chemical Co., Greenwich CT.
Example 1
A dyed light blue 30 oz./yd.2 (1 kg/m2) tufted, cut pile carpet (made from
twisted, Superba heatset, 1410 DuPont fiber, from E. I. du Pont de Nemours and
Company, Wilmington DE) was sprayed with 30% wet pickup of a bath
containing 18 g/L of N-119 Soil Resist. A flex-nip application of 250% by
weight
of a bath containing 16 g/L of SR-500 Stain Resist was then made. The carpet
was steamed at 210-212°F (99-100°C) for 2.5 min., and washed
with water. It
was then vacuum extracted to SO% wet pickup, and dried to a carpet face
temperature of 300°F (149°C). The dried carpet was tested
according to the
methods above and the results are shown in Table 2 below.
Example 2
Lightly dyed carpet as in Example 1 was sprayed with 30% wet pickup of
a bath containing 20 g/L of ZONYL 555 Soil Resist. Then a flex-nip application
of 250% by weight of a bath containing 16 g/L of SR-500 Stain Resist was made.
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The carpet was steamed at 210-212°F (99-100°C) for 2.5 min.,
and washed with
water. It was then vacuum extracted to 50% wet pickup, and dried to a carpet
face
temperature of 300°F (149°C). The dried carpet was tested
according to the
methods above and the results are shown in Table 2 below.
Example 3
Lightly dyed carpet as in Example I was given a flex-nip application of
250% by weight of a bath containing 16 g/L of SR-300 Stain Resist. It was then
sprayed with 30% wet pickup of a bath containing 20 g/L of ZONYL 555 Soil
Resist, and steamed at 210-212°F (99-100°C) for 4 min. It was
rinsed with water,
vacuum extracted to 50% wet pickup, and dried to a carpet face temperature of
300°F ( 149°C). The dried carpet was tested according to the
methods above and
the results are shown in Table 2 below.
Comparative Example A
Lightly dyed carpet as in Example I was given a flex-nip application of
250% by weight of a bath containing 14 g/L of SR-400 Stain.Resist. It was then
steamed at 210-212°F (99-100°C) for 2.5 min. It was rinsed with
water, and
vacuum extracted to 50% wet pickup. It was then sprayed with 1 S% wet pickup
of a bath containing 20 g/L of N-130 Soil Resist. It was dried to a carpet
face
temperature of 300°F (149°C) in a gas fired oven. The dried
carpet was tested
according to the methods above and the results are shown in Table 2 below.
Table 2
Carnet Testing
Test Method
!.a, b 2 3
FluorineOil/Water24 hr FD&C Shampoo-Wash
Example ContentRepellencyRed Durability
#40 Staining
Example I 11 3/6 9.5 9
1 ppm
Example 223 0/4 9.5 9.5
2 ppm
Example 330 3/3 9 2
3 ppm
Comparative349 0/3 9 6
Example ppm
A
The results in Table 2 indicate superior oil repellency in Examples I and 3,
superior water repellency in Examples 1 and 2, superior stain resistance in
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Examples 1 and 2, and superior durability of stain resistance in Examples 1
and 2,
in each case using the tandem application of the present invention when
compared
with Comparative Example A, even though the fluorine loading in the
Comparative Example is substantially higher than in Examples 1 and 2. In the
Comparative Example A intervening finishing steps were employed between
application of the stain resist and the soil resist.
Comparative Example B
To a dyed light blue 30 oz./yd.2 (1 kg/m2) tufted, cut pile carpet (made
from twisted, Superba heatset, 1410 DuPont fiber, from E. I. du Pont de
Nemours
and Company, Wilmington, DE) a flex-nip application of 250% by weight of a
bath containing both 16 g/L of SR-500 Stain Resist and 2.0 g/L of N-119 Soil
Resist at a pH of 2.0 was made. The carpet was steamed at 210-212°F (99-
100°C)
for 2.5 minutes and rinsed with water. It was then vacuum extracted to 50% wet
pickup, and dried to a carpet face temperature of 300°F (149°C).
The dried carpet
was tested according to the methods above and the results are shown in Table 3
below.
Table 3
Carpet Testine
Test Method
l.a, b 2 3
FluorineOil/Water24 hr FD&C Shampoo-Wash
Example ContentRepellencyRed Durability
#40 Staining
1 111 3/6 9.5
ppm
Comparative59 ppm 0/3 9 8.5
Example
B
The data in Table 3 indicate superior oil and water repellency, stain
resistance, and durability of stain resistance for Example 1 using the tandem
application process of the present invention when compared to Comparative
Example B in which simultaneous coapplication of the stain resist and soil
resist
was employed.
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